RESUMO
Membrane technology plays a vital, applicable, and essential role in human life and industry. The high adsorption capacity of membranes can be employed for capturing air pollutants and greenhouse gases. In this work, we tried to develop a shaped industrial form of a metal-organic framework as an adsorbent material with the ability to capture CO2 in the laboratory phase. To do so, a core/shell Nylon 6,6/La-TMA MOF nanofiber composite membrane was synthesized. This organic/inorganic nanomembrane is a kind of nonwoven electrospun fiber that was prepared using the coaxial electrospinning approach. FE-SEM, surface area calculations, nitrogen adsorption/desorption, XRD grazing incidence on thin films, and histogram diagrams were applied to assess the quality of the membrane. This composite membrane as well as pure La-TMA MOF were assessed as CO2 adsorbent materials. The CO2 adsorption abilities of the core/shell Nylon 6,6/La-TMA MOF membrane and pure La-TMA MOF were as high as 0.219 and 0.277 mmol/g, respectively. As a result of preparing the nanocomposite membrane from microtubes of La-TMA MOF, the %A of the micro La-TMA MOF (% 43.060) increased to % 48.524 for Nylon 6,6/La-TMA MOF.
RESUMO
A La-TMA metal-organic framework (MOF) made up of benzene-1,3,5-tricarboxylate and La(III) was synthesized by a different methodology compared to those in previous reports. By using various approaches, the structural characteristics and physical properties of the La-TMA MOF were analyzed. Eventually, the results showed micro-hexagonal hollow tubes with a high crystallinity grade and thermal stability (up to 400 °C) and a higher surface area compared with those from earlier reports. The BET surface area of a similar previous MOF was about 14.8 m2/g; however, in the current project, the BET surface area increased to about 34.49 m2/g and the Langmuir surface area to 42.3 m2/g.
RESUMO
To investigate the effect of different halogen substituents and leaving groups and the flexibility of ligands on the anticancer activity of copper complexes, sixteen copper(ii) complexes with eight different tridentate Schiff-base ligands containing pyridine and 3,5-halogen-substituted phenol moieties were synthesized and characterized by spectroscopic methods. Four of these complexes were also characterized by X-ray crystallography. The cytotoxicity of the complexes was determined in three different tumor cell lines (i.e. the A2780 ovarian, HCT116 colorectal and MCF7 breast cancer cell line) and in a normal primary fibroblast cell line. Complexes were demonstrated to induce a higher loss of cell viability in the ovarian carcinoma cell line (A2780) with respect to the other two tumor cell lines, and therefore the biological mechanisms underlying this loss of viability were further investigated. Complexes with ligand L1 (containing a 2-pycolylamine-type motif) were more cytotoxic than complexes with L2 (containing a 2-(2-pyridyl)ethylamine-type motif). The loss of cell viability in A2780 tumor cells was observed in the order Cu(Cl2-L1)NO3 > Cu(Cl2-L1)Cl > Cu(Br2-L1)Cl > Cu(BrCl-L1)Cl. All complexes were able to induce reactive oxygen species (ROS) that could be related to the loss of cell viability. Complexes Cu(BrCl-L1)Cl and Cu(Cl2-L1)NO3 were able to promote A2780 cell apoptosis and autophagy and for complex Cu(BrCl-L1)Cl the increase in apoptosis was due to the intrinsic pathway. Cu(Cl2-L1)Cl and Cu(Br2-L1)Cl complexes lead to cellular detachment allowing to correlate with the results of loss of cell viability. Despite the ability of the Cu(BrCl-L1)Cl complex to induce programmed cell death in A2780 cells, its therapeutic window turned out to be low making the Cu(Cl2-L1)NO3 complex the most promising candidate for additional biological applications.
